PLEASE HELP ME WITH THIS IN C$++$

Additional intructions:

Modify the time machine application to go back $-$ and $-$ forth Multiple times by entering the time desired minutes $.$ It could be that the user can move forward further or go back

For example :

Present and Future time are fixed and minutes difference are to be computed

Initial time : $5$:$15$ AM

Second time : $6$:$30$ PM

Third to succeeding iteration can be achieved by deducting or adding intervals per minutes

Third time : $4$:$30$ AM

Fourth time : $2$:$30$ AM